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Similar to 5-over denture new removable prosthodontics .ppt
5-over denture new removable prosthodontics .ppt
- 1. By : Mustafa HassanElkady Ehab Khaled Under supervision : Prof Dr : Sahar kortam
- 2. Definition The overdenture isa complete or partial denture prosthesis constructed over existing teeth, root structure and/or dental implants. The overdenture is also called “overlay denture”, “overlay prosthesis”, “superimposed prosthesis”
- 3.
- 4. Advantages of Overdentures 1-Preservation of residual ridge . • Improved occlusal stress distribution. • Edentulous mouth Bone loss of 6.6mm in 7 years. • Dentate mouth Bone loss of 0.8mm in 7 years. Mandibular bone is affected four times more than the maxillary bone. Tallgreen A Acta Odontol Scand 24: 195-239, 1966.
- 5. Mandibular bone is Mandibularbone is affected four times affected four times more than the more than the maxillary bone. maxillary bone.
- 6. Advantages of Overdentures 2-Prevent the loss of teeth. 3- Preservation of proprioceptive response: Enhance neuromascular control , occlusal awareness and biting force.
- 7. Proprioception Periodontal mechanoreceptors aresaid to allow a finer discrimination of food texture, tooth contacts and levels of functional loading. This neuromuscular coordination allow pt to have better control and greater confident in their ability to eat, drink and speak. The bite force for natural dentition is 150- 200 lb/in². Complete denture is 25 lb. and overdenture is 75 Lb.
- 8. Advantages of Overdentures 4-Stability, Support. ◦ Bone preservation, presence of natural teeth leading to less trauma to soft tissues. 5- Retention. ◦ Through Attachments, additional retention may be obtained by adding different attachment devices.
- 9. Advantages of Overdentures 6-Patientacceptance and Psychological Benefits 7- Convertibility 8-Conventional dental procedures
- 10. Disadvantages of Overdentures •Caries susceptibility.
- 11. Disadvantages of Overdentures •Bony undercuts: Limitation of the path of insertion of O. D.
- 12. Disadvantages of Overdentures •Periodontal breakdown of the abutment teeth. – Gingivitis – Periodontitis – Hyperplasia
- 13. Disadvantages of Overdentures •In adequate reduction of the abutment teeth may increased vertical dimension.
- 14. Disadvantages of Overdentures •Encroachment of the interocclusal distance. • Esthetics.
- 15. Disadvantages of Overdentures Expenseand Time consuming Bulkier Removable Prosthesis
- 16. Indications for Overdentures Fewremaining teeth are present, not suitable for fixed or RPD Mobile teeth: Reduction of unhealthy remaining periodontal teeth, decrease the C/R ratio, inturn decrease the hypermobility of teeth. Severe attrition Abnormal jaws Congenital defects Alternative treatment to single dentures
- 17. Contraindications for Overdentures If anyother prosthetic plan can give superior results In cases with poor oral hygiene. Inadequate interarch distance to accept the denture and abutments. Abutments exhibiting mobility, which exceeds grade III.
- 18. Inter-arch Space The determinationof a case to be treated with overdentures should be done with care, mounted models are extremely beneficial in determining whether there is adequate space for the overdenture, attachments or copings or bars.
- 19. Types Complete overdentures . Partialoverdentures. Fully tooth/implant supported. Tissue – tooth/implant suported. Immediate overdentures. Transitional overdentures. Definitive overdentures.
- 20. Classification of Overdentures Toothsupported Implant supported
- 21. Classification of tooth- supportedoverdentures I. According to time of placement: Immediate Transitional Definitive (Remote)
- 22. Immediate Overdenture I.O.D. is constructedprior to the preparation of abutment teeth and inserted after the preparation. When the processed denture is fitted, it is relined with cold cured acrylic in the areas around the abutment teeth to make it fit as well as possible.
- 23. Transitional Overdenture Obtaining by Convertingan already existing RPD to an O.D.
- 24. Classification of tooth- supportedoverdentures II. According to design and technique of abutment preparation: II. According to design and technique of abutment preparation: 1- Simple tooth reduction of vital abutment 1- Simple tooth reduction of vital abutment. . 2- Tooth reduction and cast coping 2- Tooth reduction and cast coping of vital abut. of vital abut. Thimble or dome- shaped Thimble or dome- shaped 3- Endodontic therapy and amalgam plug 4- Endodontic therapy with post and coping 5- Endodontic therapy with cast coping and 5- Endodontic therapy with cast coping and attachments attachments 6- Telescopic Overdenture 6- Telescopic Overdenture
- 25. Classification of tooth-supported overdentures II.According to design and technique of abutment preparation: 1- Simple tooth modification of vital abutment.
- 33. 2- Tooth reductionand cast coping of vital abut. A- Thimble-shaped coping
- 34. B- Dome shapedTooth reduction and cast coping
- 35.
- 36. 3- Endodontic therapy andamalgam plug 4- Endodontic therapy with post and cast coping
- 37. 5- Endodontic therapywith cast coping and attachments
- 38.
- 41. Gold or metalliccast Copings and telescopic crowns are a method of improving overdenture retention. These may be conical crowns (semi- parallel wall) with a friction adaptation at the marginal area of the abutment or Milled crowns for larger areas and parallel surfaces. Friction retention is more commonly used in exclusively tooth-supported overdentures that are not supported by soft tissue.
- 42.
- 44.
- 45. Abutment selection. ◦ Positionof abutments. ◦ Number of abutments. ◦ Periodontal evaluation. ◦ Endodontic evaluation. ◦ Decay or previous restorations.
- 46. Position & Numberof abutments At least one tooth per quadrant. Retained teeth should preferable not be adjacent ones. There should be several millimeters of space between the reduced tooth forms. Canines and premolars are the best overdenture abutments to reduce adverse forces at this site.
- 47. Periodontal and MobilityStatus Bone support, pocket depth, width of attached gingiva, mobility, furcation involvement, & root morphology. Minimal mobility At least 6mm of bone support Attached gingiva around the abutments Good oral hygiene Proper emergence profile to support the marginal gingiva
- 48.
- 49. Endodontic Potential and prostheticstatus • Single rooted teeth are easer to treat. • Pulpal recession • The use of restorative materials and sealants • Prior RCT already done. • Potential for RCT.
- 50. Restorative Condition Caries. Previous restorations. Crownlengthening indicated.
- 52.
- 53.
- 54.
- 55.
- 57.
- 58. Attachments An attachment isdefined as a mechanical device used for retention and stabilization of a prosthesis.
- 59. Classification of attachment 1.Acc to type Stud , bar and magnet 2. Acc to resiliency Rigid or resilient 3. Acc to location intracoronal or extracoronal 4. Acc to fabrication Precision or semi precision 5. Acc to retention Friction , mechanical, magnetic Intra radicular or extra radicular
- 60. 1. PRECISION ATTACHMENTS Readymade attachment their component are machined in a especial alloys under precise tolerance. Less wear, Standard parts, easier to repair . 2- SEMI- PRECISION ATTACHMENTS semi- precision attachment is fabricated by the direct casting of plastic, wax or refractory patterns, subject to variables of fabrication, economy. I-
- 61. II- Rigid attachments: donot allow for movement of the denture base providing adequate retention. However, may induce more torque on the abutments. Resilient attachments: allow some controlled vertical movement. They induce less torque on abutments. However, they are more complex in design and fabrication.
- 62. it’s important todifferentiate between resilient or non resilient type restoration. Abutment/tooth supported restorations are considered non-resilient or solid, while abutment and tissue- supported restorations are considered resilient.
- 63. Selection of Overdenture Attachments Availableinterarch space Cost Alignment of the roots Maintenance issue Clinical experience and personal preference
- 64. Attachment retained overdenturesare more expensive and require more work and time for their construction. They are indicated for patients exhibiting good oral hygiene and low caries index. Abutment teeth should have good periodontal condition and adequate bone support that enable them to tolerate extra stresses that may be added by the attachment.
- 65. III- Attachments forOverdentures 1. Stud attachments 2. Magnets 3. Bar attachments
- 66. Stud attachments: Consist ofmale stud that snugly fits a female housing. The stud is usually attached to the metal coping cemented over the prepared abutment, while the female housing is embedded in the fitting surface of the acrylic overdenture exactly opposite to the abutment.
- 67. ► ►Among the simplestof all attachments Among the simplest of all attachments ► ► Their retentive elements can be reactivated or replaced in the denture base. ► ► Have applications for both root & implant supported Have applications for both root & implant supported prosthesis prosthesis
- 68. * * Brewer &Morrow (1980), Brewer & Morrow (1980), classified stud attachments into: classified stud attachments into: Resilient Stud attachments Rigid stud attachments * Designed so as to permit or provide for a “controlled” movement. * They act as safety valve for any overload situations. * Do not allow any movement * Indicated when interocclusal space is limited & when no potential movement of the overdenture is required
- 69. Rigid stud attachments Stud atts.Work best when they are Aligned with one another and the path of insertion of the denture
- 70.
- 71. Three categories maybe considered: 1-Location 2-Function 3-Retention
- 72. Overdenture Attachments Intracoronal stud attachments. Extracoronalstud attachments. Intraradicular attachment. Extraradicular attachment. Bar attachment. 1-Location 1-Location
- 73. Intracoronal attachments: Intracoronal attachmentsare incorporated entirely within the contour of the crown. excessive tooth reduction and compromised embrasures, which result in oral hygiene and periodontal situation problems. In addition, all intracoronal attachments are non-resilient.
- 75. b. Extracoronal attachments allof their mechanism outside the contour of a tooth. minimal tooth reduction is necessary
- 76.
- 77. Extracoronal attachment Extracoronal attachmentact as Stress Breakers Stress Breakers RPD having a movable joint between the direct retainer and the denture base This joint may be in the form of hinges, ball and socket devices or sleeves and cylinders Hinged type stress breakers allows vertical and hinge movement of the base
- 78. Hinged type stressbreakers allows vertical and hinge movement of the base to prevent direct transmission of tipping forces to the abutment A- Dalbo extra-coronal precision attachment device B- Chrisman intra-coronal retainer
- 79. Advantages • Esthetics • Hygiene •Stress distribution: Deep rest, Directs stress along long axis • Single path of movement
- 80. • Comfort • Fewerlingual components
- 81. Disadvantages Extra tooth preparationfor intracoronal attachments
- 82. Disadvantages Can’t place flangein some undercuts in overdenture attachments Cost
- 83. Not Easy constructed Parallelism Casting Processing NeedsTissue base impression Relating Base to teeth
- 84. Contraindications Short clinical crowns Largepulps Dexterity problems Bruxers?
- 85. Not Easy constructed ParallelismCasting Processing acrylic Tissue base impression Relating Base to teeth Contraindications Short clinical crowns Large pulps Dexterity problems Bruxers?
- 86. Intraradicular attachment Metal andplastic sections (male) are incorporated within the root
- 87.
- 88. Intraradicular attachment Metal section(female ) is incorporated within the root
- 89. * * Chee &Donavan (1993), Chee & Donavan (1993), classified stud attachments into: classified stud attachments into: Intra-radicular Extra-radicular * The male portion (patrix) forms part of the denture base and engages a special depression within the root contour or implant * The male portion (patrix) projects from the root surface of the preparation or implant. * Logic * Zest * Rotherman attachment * Dalla Bona * Micro Fix
- 90.
- 91. Attachments for Overdentures Types 1.Stud attachments 2. Magnets 3. Bar attachments
- 92. Magnets Magnetic retention foroverdenture: One magnet pole is cemented in a prepared cavity in the endodontically prepared tooth, while the other pole is attached to the denture base opposite to it.
- 93.
- 94. 2-Function it’s important todifferentiate between resilient or non resilient type restoration. Abutment/tooth supported restorations are considered non-resilient or solid, while abutment and tissue-supported restorations are considered resilient.
- 95. 3- Retention ofattachments It can be obtained by: frictional. mechanical. frictional and mechanical. Magnets.
- 96. Another distinction ismade between mechanical and magnetic attachments. The difference lies in the mechanism of retention as the nomenclature implies. Magnets Keepers
- 98. Attachments for Overdentures Types 1.Stud attachments 2. Magnets 3. Bar attachments
- 99. Bar attachments: A barattachment is in the form of a bar contoured to run parallel and overlie the residual ridge connecting the abutments together. The bar provides support and retention for the overdenture and splinting of abutment teeth. (or implants)
- 100. Bar attachment Sleeve Clip, intowhich the bar will slot Bar
- 101. • Should notcause food entrapment • Should not cause Blanching of the tissues • Should not cause encourage tissue proliferation
- 102. ** Adequate interocclusal distance **Adequateclearance beneath the bar ** Adequate Bony support ** Bar should follow ridge contour
- 103. Dolder bar Single sleevebar Gilmore bar Multi-sleeve system Master cast to show position and alignment of bar
- 104. Bar attachment •Retention tagsproject in the long axis of the bar, has been found to be somewhat more fracture resistant- •The buccoling. tags resist rotational force more than tagging parallel with the bar. •Tagging encroaches arrangement of artificial teeth .
- 105. Bar attachments areeither in the form of: Bar units: rigid fixation where there is no movement between bar and overlying sleeve “ Tooth borne” Bar joints: Permit rotational movement between sleeve and bar, utilizing some of the residual ridge for support “tooth tissue borne”.
- 106. Bar Joints BarUnits esilient version ome rotational movement ween the bar & the sleeve more R.R support Less torque on teeth * Rigid version * provides rigid fixation – no movement between the bar & the sleeve indicated when saddle gap is long ► ► Dolder bar attachment Dolder bar attachment Resilient Resilient Rigid Rigid
- 107.
- 108.
- 109. Treatment Planning Patient Selection ◦Medical History. ◦ Oral Hygiene. ◦ Compliance. ◦ Motivation. Abutment selection. ◦ Position. ◦ Number of abutments ◦ Periodontal evaluation. ◦ Endodontic evaluation. ◦ Decay or previous restorations. Inter-arch space.
- 110. Choices of Overdenture Choicesof Overdenture Abutment Abutment 1. 1. Amalgam plug Amalgam plug 2. 2. Cast dowel dome Cast dowel dome 3. 3. Attachment on the Attachment on the abutment root abutment root ctors to be considered ctors to be considered Cost Cost Abutment condition Abutment condition Does the patient have high risk Does the patient have high risk to caries? to caries? Do we need extra retention to Do we need extra retention to compensate the loss of peripheral compensate the loss of peripheral seal from ridge/soft tissue undercut seal from ridge/soft tissue undercut
- 111. A- crown rootratio. B- type of coping. C- vertical space available. D- number of teeth present. E- amount of tooth support. F- location of abutments. Attachment selection: Attachment selection: it based on: it based on:
- 112. G- location ofthe strongest abutments. H- whether the overdenture is to be a tooth-supported or tooth-tissue supported. J- type of the opposing dentition whether complete denture, overdenture, fixed appliances or natural dentition. K- the maintenance problems and of least importance the cost.
- 113. Clinical Procedures I-Abutment preparation: -Crownreduction and contouring with or without endodontic treatment - Periodontal treatment. II-Primary impression: alginate impression in stock tray. III- Special trays constructed on primary cast.
- 114. Preparing the Abutments 1.Maximum Reduction of the Coronal Portion 2. Crown-root ratio 3. No interference with artificial tooth placement 4. Restoration and polishing Crown reduction
- 116. Clinical Procedures III- Secondaryimpression Made using rubber base stone
- 117. Clinical Procedures Secondary impressionis made using rubber base, pour stone casts Wax patterns for copings Casting into metal Copings are cemented on prepared abutments Another Impressions are made to obtain casts for the coping-covered abutments.
- 120. Another Impressions aremade to obtain casts for the coping covered abutments
- 121. Another Impressions aremade to obtain casts for the coping covered abutments Upper special tray which is spaced for an alginate impression technique.
- 122. Another Impressions aremade to obtain casts for the coping covered abutments If precision attachments are used. A special tray is used with either impression paste or elastomers depending on the presence of undercuts. The tray has a window over each of the abutments, this ensures any excess material flows out, without displacing any of the tissues
- 123. Clinical Procedures IV- JawRelation Records: Mounting of upper cast on semi ad. art. by face-bow record mounting of lower cast by centric occluding relation setting up of teeth.
- 124. Clinical Procedures Fitting surfaceof the trial denture should be relieved over the abutments for proper denture settling check for stability check vertical dimension check occlusion. V- Try-in:
- 125. Clinical Procedures VI- Dentureprocessing VII- Denture insertion VIII- Post-insertion care
- 126.
- 127. “Passive” Contact Abutment contactsdenture in function only Fitting surface of the trial denture should be relieved over the abutments for proper denture settling, avoid pressure on the gingival margin of the abutments RESTING FUNCTION
- 128.
- 129. Maintenance Oral Hygiene Brushing Denture kept in tap water when not use. Frequent recalls For post insertion care and prophylactic care of abutments. (fluoride application)
- 192.
Editor's Notes
- #67 Click: Stud attachments are considered simple and relatively small when compared to other attachments Click: They have applications for both root Click and implant-supported prosthesis Click Their retentive elements can be reactivated or replaced in the denture base.
- #68 Click Stud attachments have been classified according to resiliency into Click Resilient & Rigid Click * Designed so as to permit or provide for a “controlled” movement.* They act as safety valve for any overload situations. Click The most common resilient stud attachments are the ball & socket types. Examples of which are the flexi-overdenture attachment & the OT-cap attachment Click Rigid attachments on the other hand do not allow any movement. They* Indicated when interocclusal space is limited & when no potential movement of the overdenture is required. Click Micro-fix is an example.
- #89 Click depending on the location of the patrix, Stud attachments are classified into Click intra & Extra-radicular Click In the intra-radicular, The male portion (patrix) forms part of the denture base and engages a special depression within the root contour or implant Click In the extra-radicular, the patrix projects from the root surface of the preparation or implant. Click the logic attachment and the Click Zest are Examples of intra-radicular attachments examples of the extra-radicular attachments include Click Rotherman, Click Micro-fix and the Click Dalla Bona
- #96 - CLICK Another distinction is made between mechanical and magnetic attachments. The difference lies in the mechanism of retention as the nomenclature implies. CLICK Keepers are usually attached to teeth or implants. CLICK Magnets are incorporated in the superstructure.
- #100 wallet
- #110 Abutment roots are long and parallel-sided can be use to attachment. Large expose dentine surface are susceptible to caries, vigorous brushing and occlusal wear. Coping could provide some caries protection but the margin area can still get caries.